/**
 * 导出页面为PDF格式
 * */
import html2Canvas from 'html2canvas'
import JsPDF from 'jspdf'

export default {
    install(Vue) {
        Vue.prototype.getPdf = function (title) {
            html2Canvas(document.querySelector('#pdfDom'), {
                allowTaint: true
            }).then(function (canvas) {
                    let contentWidth = canvas.width;
                    let contentHeight = canvas.height;
                    let pageHeight = contentWidth / 592.28 * 841.89;
                    let leftHeight = contentHeight;
                    let position = 0;
                    let imgWidth = 595.28;
                    let imgHeight = 592.28 / contentWidth * contentHeight;
                    let pageData = canvas.toDataURL('image/jpeg', 1.0);
                    let PDF = new JsPDF('', 'pt', 'a4');
                    if (leftHeight < pageHeight) {
                        PDF.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight)
                    } else {
                        while (leftHeight > 0) {
                            PDF.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight);
                            leftHeight -= pageHeight;
                            position -= 841.89;
                            if (leftHeight > 0) {
                                PDF.addPage()
                            }
                        }
                    }
                    PDF.save(title + '.pdf')
                }
            )
        }
    }
}
